CHAPTER 19 FCAN CONTROLLER (V850/SC3)
User’s Manual U15109EJ3V0UD
598
(2/2)
(a) Read
GOM
Status of global operation mode
0
CAN module is reset and access to CAN module register
Note 1
is prohibited
1
CAN module operation is enabled and access to CAN module register
Note 1
is
enabled
•
The GOM bit controls the method the memory is accessed by the MAC and CAN module
operation status.
•
When GOM bit = 0
•
All CAN modules are reset
•
Access to CAN module register disabled (if accessed, a MAC error interrupt occurs)
Note 2
•
Access to temporary buffer enabled
•
Access to message buffer area enabled
•
When GOM bit = 1
•
Access to CAN module register enabled
Note 3
•
Access to temporary buffer prohibited (if accessed, a MAC error interrupt occurs)
•
Access to message buffer area enabled
•
The GOM bit is cleared (0) only when all the CAN modules are in the initial mode (the INIT
bit of the CnCTRL register is 1). Even if the GOM bit is cleared when there is a CAN
module not in the initial mode, the GOM bit remains set (1).
•
To clear (0) the GOM bit, first set (1) the INIT bit of the CnCTRL register, and then set (1)
the EFSD bit. Do not manipulate the GOM bit and EFSD bit simultaneously.
Notes 1.
Register with a name starting with “Cn” (n = 1, 2)
2.
The CGCS register can be accessed.
Write accessing the CGMSS register is prohibited. If the CGMSS register is write-
accessed, the wrong search result is reflected in the CGMSR register.
3.
Write accessing the CGCS register is prohibited.
Write accessing the CGMSS register is possible.